\documentclass[multi=tikzpicture]{standalone}

\usepackage[T1]{fontenc}
\usepackage{pslatex}
\renewcommand*\ttdefault{txtt}
\usepackage{tikz-timing}
\usetikztiminglibrary[rising arrows]{clockarrows}
\usetikztiminglibrary{either}

\begin{document}

\begin{tikztimingtable}[
font=\tt,
timing/yunit=3ex,
timing/xunit=3ex,
timing/text format=\raisebox{.4ex}\strut\tt\Large,
timing/u/background/.style={fill=lightgray},
timing/e/background/.style={fill=lightgray}
]
  & .1H 2H 2L  2D{b0}  2D{b1}   2D{b2} 2D{b3} 2D{b4} 2D{b5}  2D{b6} 2D{b7} 3H 1.9H  \\
\end{tikztimingtable}

\end{document}
